diff --git a/Boards.h b/Boards.h
index ef2b8c5..c059cd6 100644
--- a/Boards.h
+++ b/Boards.h
@@ -149,6 +149,10 @@
     #endif
   #endif
 
+  #define LORA_PA_UNKNOWN  0x00
+  #define LORA_PA_GC1109   0x01
+  #define LORA_PA_KCT8103L 0x02
+
   #define HAS_DISPLAY false
   #define HAS_BLUETOOTH false
   #define HAS_BLE false
@@ -251,7 +255,7 @@
         #define HAS_TCXO true
         #define HAS_BUSY true
         #define DIO2_AS_RF_SWITCH true
-        #define OCP_TUNED 0x18
+        #define OCP_TUNED 0x28
         const int pin_busy = 32;
         const int pin_dio = 33;
         const int pin_tcxo_enable = -1;
@@ -357,7 +361,7 @@
       #define HAS_SLEEP true
       #define PIN_WAKEUP GPIO_NUM_0
       #define WAKEUP_LEVEL 0
-      #define OCP_TUNED 0x18
+      #define OCP_TUNED 0x28
 
       const int pin_btn_usr1 = 0;
 
@@ -399,8 +403,9 @@
       #define HAS_LORA_LNA true
       #define PIN_WAKEUP GPIO_NUM_0
       #define WAKEUP_LEVEL 0
-      #define OCP_TUNED 0x18
+      #define OCP_TUNED 0x28
       #define Vext GPIO_NUM_36
+      #define LORA_PA_MODEL LORA_PA_UNKNOWN;
 
       const int pin_btn_usr1 = 0;
 
@@ -422,14 +427,17 @@
 
       #define LORA_LNA_GAIN  17
       #define LORA_LNA_GVT   12
-      #define LORA_PA_GC1109 true
       #define LORA_PA_PWR_EN  7
-      #define LORA_PA_CSD     2
-      #define LORA_PA_CPS    46
+      #define LORA_PA_CSD     2 // Same pin on GC1109
+      #define LORA_PA_CPS    46 // Same pin on GC1109
+      #define LORA_PA_CTX     5 // Only used on KCT8103
 
       #define PA_MAX_OUTPUT  28
       #define PA_GAIN_POINTS 22
-      #define PA_GAIN_VALUES 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 10, 10, 9, 9, 8, 7
+      
+      #define LORA_LNA_KCT8103L_GAIN 21
+      const int PA_GC1109_VALUES[PA_GAIN_POINTS] =   {11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 10, 10,  9, 9, 8, 7};
+      const int PA_KCT8103L_VALUES[PA_GAIN_POINTS] = {13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 12, 12, 11, 11, 10, 9, 8, 7};
 
       const int pin_cs = 8;
       const int pin_busy = 13;
@@ -618,7 +626,7 @@
       #define DIO2_AS_RF_SWITCH true
       #define HAS_BUSY true
       #define HAS_TCXO true
-      #define OCP_TUNED 0x18
+      #define OCP_TUNED 0x28
 
       #define HAS_DISPLAY true
       #define HAS_CONSOLE true
@@ -921,7 +929,7 @@
   // Default OCP value if not specified
   // in board configuration
   #ifndef OCP_TUNED
-    #define OCP_TUNED 0x18
+    #define OCP_TUNED 0x28
   #endif
 
   #ifndef NP_M
diff --git a/Utilities.h b/Utilities.h
index 8892f59..f6fbac2 100644
--- a/Utilities.h
+++ b/Utilities.h
@@ -1287,11 +1287,33 @@ int getTxPower() {
 }
 
 #if HAS_LORA_PA
-	const int tx_gain[PA_GAIN_POINTS] = {PA_GAIN_VALUES};
+	#if BOARD_MODEL == BOARD_HELTEC32_V4
+		bool pa_values_determined = false;
+		int tx_gain[PA_GAIN_POINTS] = {100};
+	#else
+		bool pa_values_determined = true;
+		const int tx_gain[PA_GAIN_POINTS] = {PA_GAIN_VALUES};
+	#endif
 #endif
 
+extern uint8_t lora_pa_model;
+void determine_pa_values() {
+	#if BOARD_MODEL == BOARD_HELTEC32_V4
+		if (lora_pa_model == LORA_PA_GC1109) {
+			for (int i=0; i < PA_GAIN_POINTS; i++) { tx_gain[i] = PA_GC1109_VALUES[i]; }
+			pa_values_determined = true;
+			for (int i=0; i < PA_GAIN_POINTS; i++) { Serial.print(" "); Serial.printf("%d", tx_gain[i]); }
+		} else if (lora_pa_model == LORA_PA_KCT8103L) {
+			for (int i=0; i < PA_GAIN_POINTS; i++) { tx_gain[i] = PA_KCT8103L_VALUES[i]; }
+			pa_values_determined = true;
+			for (int i=0; i < PA_GAIN_POINTS; i++) { Serial.print(" "); Serial.printf("%d", tx_gain[i]); }
+		}
+	#endif
+}
+
 int map_target_power_to_modem_output(int target_tx_power) {
 	#if HAS_LORA_PA
+		if (!pa_values_determined) { determine_pa_values(); }
 		int modem_output_dbm = -9;
 		for (int i = 0; i < PA_GAIN_POINTS; i++) {
 			int gain = tx_gain[i];
diff --git a/sx126x.cpp b/sx126x.cpp
index f8da5fa..97ca045 100644
--- a/sx126x.cpp
+++ b/sx126x.cpp
@@ -96,6 +96,14 @@
   #define SPI spiModem
 #endif
 
+#if HAS_LORA_PA
+  uint8_t lora_pa_model = LORA_PA_MODEL;
+#endif
+
+#if HAS_LORA_LNA
+  int lora_lna_gain = LORA_LNA_GAIN;
+#endif
+
 extern SPIClass SPI;
 
 #define MAX_PKT_LENGTH 255
@@ -358,7 +366,22 @@ int sx126x::begin(long frequency) {
   setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode);
 
   #if HAS_LORA_PA
-    #if LORA_PA_GC1109
+    if (lora_pa_model == LORA_PA_UNKNOWN) {
+      #if BOARD_MODEL == BOARD_HELTEC32_V4
+        
+        pinMode(LORA_PA_PWR_EN, OUTPUT);
+        pinMode(LORA_PA_CSD, INPUT);
+        digitalWrite(LORA_PA_PWR_EN, HIGH); delay(5);
+        if (digitalRead(LORA_PA_CSD) == HIGH) {
+          lora_pa_model = LORA_PA_KCT8103L;
+          lora_lna_gain = LORA_LNA_KCT8103L_GAIN;
+        } else {
+          lora_pa_model = LORA_PA_GC1109;
+        }
+      #endif
+    }
+
+    if (lora_pa_model == LORA_PA_GC1109) {
       // Enable Vfem_ctl for supply to
       // PA power net.
       pinMode(LORA_PA_PWR_EN, OUTPUT);
@@ -383,7 +406,26 @@ int sx126x::begin(long frequency) {
       // is driven by the SX1262 DIO2
       // pin directly, so we do not
       // need to manually raise this.
-    #endif
+
+    } else if (lora_pa_model == LORA_PA_KCT8103L) {
+      // Enable Vfem_ctl for supply to
+      // PA power net.
+      pinMode(LORA_PA_PWR_EN, OUTPUT);
+      digitalWrite(LORA_PA_PWR_EN, HIGH);
+
+      // Enable KCT8103L chip
+      pinMode(LORA_PA_CSD, OUTPUT);
+      digitalWrite(LORA_PA_CSD, HIGH);
+
+      // Enable receive LNA
+      pinMode(LORA_PA_CTX, OUTPUT);
+      digitalWrite(LORA_PA_CTX, LOW);
+
+      // On Heltec V4.3, the PA CPS pin
+      // is driven by the SX1262 DIO2
+      // pin directly, so we do not
+      // need to manually raise this.
+    }
   #endif
 
   return 1;
@@ -393,13 +435,15 @@ void sx126x::end() { sleep(); SPI.end(); _preinit_done = false; }
 
 int sx126x::beginPacket(int implicitHeader) {
   #if HAS_LORA_PA
-    #if LORA_PA_GC1109
+    if (lora_pa_model == LORA_PA_GC1109) {
       // Enable PA CPS for transmit
       // digitalWrite(LORA_PA_CPS, HIGH);
       // Disabled since we're keeping it
       // on permanently as long as the
       // radio is powered up.
-    #endif
+    } else if (lora_pa_model == LORA_PA_KCT8103L) {
+      digitalWrite(LORA_PA_CTX, HIGH);
+    }
   #endif
 
   standby();
@@ -487,7 +531,7 @@ int ISR_VECT sx126x::currentRssi() {
   executeOpcodeRead(OP_CURRENT_RSSI_6X, &byte, 1);
   int rssi = -(int(byte)) / 2;
   #if HAS_LORA_LNA
-    rssi -= LORA_LNA_GAIN;
+    rssi -= lora_lna_gain;
   #endif
   return rssi;
 }
@@ -503,7 +547,7 @@ int ISR_VECT sx126x::packetRssi() {
   executeOpcodeRead(OP_PACKET_STATUS_6X, buf, 3);
   int pkt_rssi = -buf[0] / 2;
   #if HAS_LORA_LNA
-    pkt_rssi -= LORA_LNA_GAIN;
+    pkt_rssi -= lora_lna_gain;
   #endif
   return pkt_rssi;
 }
@@ -610,7 +654,7 @@ void sx126x::onReceive(void(*callback)(int)){
 
 void sx126x::receive(int size) {
   #if HAS_LORA_PA
-    #if LORA_PA_GC1109
+    if (lora_pa_model == LORA_PA_GC1109) {
       // Disable PA CPS for receive
       // digitalWrite(LORA_PA_CPS, LOW);
       // That turned out to be a bad idea.
@@ -618,7 +662,9 @@ void sx126x::receive(int size) {
       // on and off too quickly. We'll keep
       // it on permanently, as long as the
       // radio is powered up.
-    #endif
+    } else if (lora_pa_model == LORA_PA_KCT8103L) {
+      digitalWrite(LORA_PA_CTX, LOW);
+    }
   #endif
 
   if (size > 0) {